Version 7.0.0

• Rewrite based on the API Copyleft License, in the style of the Blue Oak Model License and Polyform Project licenses.
• Add an explicit exception for prototypes.
• Add an explicit exception for reverse engineering closed software.
• Numerous improvements to copyleft rules.
• Use string-interpolation-style $-sigil placeholders.

Version 7.0.0-pre.1

• Rewrite based on the API Copyleft License, the style of the Blue Oak Model License and Polyform Project licenses.
• Add an explicit exception for prototypes.
• Numerous improvements to copyleft rules.

Version 6.0.0

• Improved, generalized and clarified contribution rules.
• Broadened and simplified patent defensive termination.

v4.0.0

• Use "application" instead of "program" in Rule 2.

3.0.0

• Require "contribution" of source code, rather than "release", for clarity.
• Extensively broader Rule 3, requiring contribution of source code for software developed, deployed, monitored, or run.